Package org.pentaho.aggdes.algorithm

Defines the interface of the Aggregate Designer algorithm and supporting classes.

See: Description

Interface Summary

Interface	Description
Algorithm	Algorithm that takes a star schema and recommends a set of aggregate tables.
Algorithm.CostBenefit	Collection of metrics describing the cost and benefit of instantiating a particular Aggregate.
Progress	Callback to report progress.
Result	Recommendations produced by an aggregate table advisor job.

Enum Summary

Enum	Description
Algorithm.ParameterEnum	Enumeration of parameters common to all algorithms.

Package org.pentaho.aggdes.algorithm Description

Defines the interface of the Aggregate Designer algorithm and supporting classes.

The Aggregate Designer consists of a number of components:

• The schema loader component (org.pentaho.aggdes.algorithm.SchemaLoader) reads a star schema and presents the algorithm with a org.pentaho.aggdes.algorithm.Schema object and embedded org.pentaho.aggdes.algorithm.Table and org.pentaho.aggdes.algorithm.Attribute objects.
• The algorithm component (Algorithm) tries to find the most efficient set of aggregates for a given schema. A set of aggregates is efficient if it enables any expected query to evaluate quickly yet has a reasonable cost in terms of disk space and load time.
• The result handler component (org.pentaho.aggdes.output.ResultHandler) converts the result of the algorithm into a useful form such as a script of CREATE TABLE statements to create aggregate tables and INSERT statements to populate them. A result handler is not necessary if you are invoking the algorithm programmatically and your program will process the (Result)object produced by the algorithm itself.

Each of the components is specified a particular Java interface that extends org.pentaho.aggdes.algorithm.Component. There is a default implementation for each component, but you can provide your own.

There is a command-line utility org.pentaho.aggdes.algorithm.Main to allow you to invoke the algorithm. You can choose which implementation of each component, and provide parameters to each component.